Transit Signal Priority in Small-Medium Size Cities
This study is unique since Transit Signal Priority (TSP) has mainly been applied in larger metropolitan areas where demand for transit service is moderate to high and bus headways are less than 15 minutes. TSP in larger metropolitan areas is implemented to expedite the movement of buses with high occupancy, thus justifying any negative impacts on other traffic and lowering the overall person-delay at intersections. Transit agencies in small-medium size cities on the other hand, have fewer users and operate at less frequency, with headways greater than 30 minutes. During peak periods, traffic congestion causes missed connections at transfer points and can increase the transit rider's total trip time by as much as one hour. TSP could be used in small-medium size cities to alleviate missed connections, enhance service, and possibly attract more transit riders. This study provides a theoretical evaluation of TSP strategies in a small-medium size city. Several scenarios are evaluated, involving two TSP strategies (early green and extended green), existing and reduced bus headways, and two traffic peak periods. The study findings could give practitioners information on TSP implementation in a similar small-medium size city. Results of the study indicated potential bus travel time savings as high as 14 percent, with a decrease in bus stopped delay as high as 38 percent. Impacts to the local system were investigated as well. Side-street person-delay increased as much as 14 percent during the afternoon peak. More information about this project is available at www.atacenter.org. TRB PresentationKiel Ova presented this research at TRB's 81st Annual Meeting Session 369—Issues in Transit Priority on January 15, 2002 in Washington, D.C.   |
In this issue...
 |
ATAC's researchers recently completed a study using a microscopic traffic simulation model, VISSIM, to model transit signal priority algorithms in the downtown region of Fargo, North Dakota.